Vadadustat

Iron supplements and iron-containing phosphate binders: Administer VAFSEO at least 1 hour before products containing iron. ( 7.1 ) Non-iron-containing phosphate binders: Administer VAFSEO at least 1 hour before or 2 hours after non-iron-containing phosphate binders. ( 7.1 ) BCRP substrates: Monitor for signs of substrate adverse reactions and consider substrate dose reduction. ( 7.2 ) Statins: Monitor for statin-related adverse reactions ( 7.2 ).

7.1 Effect of Other Drugs on VAFSEO Table 3 describes clinically significant drug interactions where concomitant use of another drug affects VAFSEO. Table 3 Drug Interactions with VAFSEO that Affect Vadadustat Exposure Iron supplements and phosphate binders Clinical Effect Co-administration with oral iron supplements, products containing iron, or phosphate binders decreases the exposure of vadadustat [ see Clinical Pharmacology ( 12.3 )] , which may reduce the effectiveness of VAFSEO.

Prevention or Management Stagger administration when VAFSEO is used with oral iron supplements, products containing iron, iron-containing phosphate binders, or non-iron-containing phosphate binders [see Dosage and Administration ( 2.5 )] .

Examples * Iron supplements : ferric citrate, ferrous sulfate, sodium ferrous citrate Iron-containing phosphate binders : ferric citrate, sucroferric oxyhydroxide Non-iron-containing phosphate binders : calcium acetate, sevelamer carbonate Organic anion transporter (OAT) OAT1/OAT3 inhibitors Clinical Effect Co-administration with OAT1/OAT3 (Organic Anion Transporter) inhibitors may increase the area under the concentration curve (AUC) of vadadustat [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of VAFSEO adverse reactions. Prevention or Management Closely monitor for too large or too rapid an increase in Hb response and for adverse reactions.

Examples * OAT1 inhibitors: probenecid, rifampicin OAT3 inhibitors: gemfibrozil, probenecid, teriflunomide * These examples are not a comprehensive list of all possible drugs that may fit this category.

7.2 Effect of VAFSEO on Other Drugs Table 4 describes clinically significant drug interactions where VAFSEO affects the co-administered drug. Table 4 Drug Interactions with VAFSEO that affect co-administered drugs BCRP substrates Clinical Effect Vadadustat may increase the exposure of BCRP substrates [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of adverse reactions related to the BCRP substrate. Prevention or Management Monitor for signs of adverse effects of the co-administered BCRP substrate and reduce substrates’ dosage in accordance with their approved product labeling, if needed.

Example * sulfasalazine Statins Clinical Effect Vadadustat increases the maximal concentration (C max ) and AUC of some statins when co-administered [see Clinical Pharmacology ( 12.3 )] . Prevention or Management Monitor for possible statin-related adverse reactions. Concomitant Drug Name Recommendation Simvastatin Starting dose of simvastatin should be 5 mg/day. Maximum daily dose of simvastatin not to exceed 20 mg. Rosuvastatin Maximum daily dose of rosuvastatin not to exceed 5 mg.

OAT3 substrates Clinical Effect Vadadustat may increase the exposure of co-administered OAT3 substrates [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of adverse reactions related to these substrates. Prevention or Management Monitor for signs of adverse reactions of the co-administered OAT3 substrates and adjust substrates’ dosage in accordance with their approved product labeling, if needed. Examples * cefaclor, ceftizoxime, famotidine, furosemide, oseltamivir carboxylate, penicillin G, sitagliptin * These examples are not a comprehensive list of all possible drugs that may fit this category.

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to VAFSEO during pregnancy. Health care providers and patients are encouraged to report pregnancies by calling 1-844-445-3799. Risk Summary Available data with VAFSEO use in pregnant women are insufficient to establish a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. There are risks to the mother and fetus associated with CKD (see Clinical Considerations) .

Vadadustat administration orally to pregnant rats and rabbits during the period of organogenesis was associated with reduced fetal weight at doses that caused maternal toxicity. In rat and rabbit studies, vadadustat was not teratogenic (see Data) . The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.

VAFSEO should only be used during pregnancy if the benefit justifies the potential risk to the fetus. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk: CKD in pregnancy increases the risk for maternal hypertension, preeclampsia, miscarriage, stillbirth, preterm delivery, low birth weight infants, and polyhydramnios. Data Animal Data Vadadustat decreased fetal weight and reduced fetal skeletal ossification in rats at a dose of 160 mg/kg/day (1.7 times the maximum recommended human dose [MRHD] based on AUC), which was associated with maternal toxicity defined by reduced body weight gain and food consumption.

Vadadustat was orally administered to pregnant rabbits at doses of 10, 25, or 50 mg/kg/day from gestation day 6 until gestation day 18 during the period of organogenesis. Vadadustat administration at 50 mg/kg/day resulted in maternal toxicity of reduced body weight gain, but no adverse effects on embryofetal development were observed at doses less than or equal to 50 mg/kg/day (1.5 times the MRHD based on AUC). In a pre- and postnatal development study, pregnant rats were dosed orally with vadadustat 20, 40, or 80 mg/kg/day from implantation until weaning (gestation day 6 to lactation day 20) at 20, 40, or 80 mg/kg/day.

There were decreased body weights of offspring at the dose of 80 mg/kg/day but no adverse effects were observed at doses less than or equal to 80 mg/kg/day (0.3 times the…